Protective casing



FIG. 1 is a front perspective view of a protective casing, showing mynew design, and including a lower portion shown herein and throughout inbroken lines for illustrative purposes only and forming no part of theclaimed design;

FIG. 2 is front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a side view thereof taken from the right of FIG. 2;

FIG. 5 is a side view thereof taken from the left of FIG. 2;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

I claim, the ornamental design for a protective casing, as shown anddescribed.